fix: unlock dates ignore leap years

internal/circulating_supply_test.go

@@ -18,9 +18,9 @@ func TestCirculatingSupply(t *testing.T) {
 		{oneYearAfterTGEMinusOneDay, 220_824_349_667_524},
 		{oneYearAfterTGE, 398_395_290_749_715},
 		{oneYearAfterTGEPlusOneDay, 399_602_581_376_425},
-		{twoYearsAfterTGE, 833432444153745},
-		{threeYearsAfterTGE, 987593533203745},
-		{fourYearsAfterTGE, 1079986906381924},
+		{twoYearsAfterTGE, 832939859033664},
+		{threeYearsAfterTGE, 987338016490616},
+		{fourYearsAfterTGE, 1079918280757792},
 	}
 	for _, tc := range testCases {
 		t.Run(tc.time.String(), func(t *testing.T) {
@@ -82,7 +82,7 @@ func Test_coreContributorsCirculating(t *testing.T) {
 		{oneDayAfterTGE, 0},
 		{oneYearAfterTGEMinusOneDay, 0},         // one day before tokens unlock.
 		{oneYearAfterTGE, coreContributors / 3}, // tokens unlock on October 30th, 2024.
-		{twoYearsAfterTGE, 117_738_314_725_882},
+		{twoYearsAfterTGE, 117_577_249_999_855},
 		{threeYearsAfterTGE, coreContributors},
 		{fourYearsAfterTGE, coreContributors},
 	}
@@ -104,8 +104,8 @@ func Test_ecosystemCirculating(t *testing.T) {
 		{TGE, .25 * ecosystem},
 		{oneDayAfterTGE, .25 * ecosystem},
 		{oneYearAfterTGE, .25 * ecosystem},
-		{twoYearsAfterTGE, 134_155_879_274_657},
-		{threeYearsAfterTGE, 201_142_057_024_657},
+		{twoYearsAfterTGE, 133_972_355_500_000},
+		{threeYearsAfterTGE, 200_958_533_250_000},
 		{fourYearsAfterTGE, ecosystem},
 	}
 	for _, tc := range testCases {

internal/dates.go

@@ -18,9 +18,12 @@ var (
 	// See https://www.mintscan.io/celestia/block/8662012
 	cip41ActivationDate = time.Date(2025, time.November, 24, 0, 0, 0, 0, time.UTC)
 
-	// TODO: verify these dates. The unlock dates may not be exactly N years
-	// after TGE. Instead, they may be N * 365 days after.
-	twoYearsAfterTGE   = TGE.AddDate(2, 0, 0)
-	threeYearsAfterTGE = TGE.AddDate(3, 0, 0)
-	fourYearsAfterTGE  = TGE.AddDate(4, 0, 0)
+	// Unlock dates are N * 365 days after TGE (not N calendar years) because
+	// vesting accounts do not account for leap years. The vesting accounts in
+	// the mainnet genesis file have end times on October 30th: one year after
+	// TGE for delayed vesting accounts, two or three years after TGE for
+	// continuous vesting accounts.
+	twoYearsAfterTGE   = TGE.AddDate(0, 0, 2*365) // October 30, 2025
+	threeYearsAfterTGE = TGE.AddDate(0, 0, 3*365) // October 30, 2026
+	fourYearsAfterTGE  = TGE.AddDate(0, 0, 4*365) // October 30, 2027
 )

internal/dates_test.go

@@ -0,0 +1,32 @@
+package internal
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+)
+
+// TestUnlockDates verifies that unlock dates are computed as N * 365 days
+// after TGE, ignoring leap years. Vesting accounts in the mainnet genesis file
+// have end times of October 30th (not October 31st) because they do not
+// account for the leap day on February 29th, 2024.
+// See https://github.com/celestiaorg/supply/issues/35
+func TestUnlockDates(t *testing.T) {
+	type testCase struct {
+		name string
+		got  time.Time
+		want time.Time
+	}
+	testCases := []testCase{
+		{"oneYearAfterTGE", oneYearAfterTGE, time.Date(2024, time.October, 30, 0, 0, 0, 0, time.UTC)},
+		{"twoYearsAfterTGE", twoYearsAfterTGE, time.Date(2025, time.October, 30, 0, 0, 0, 0, time.UTC)},
+		{"threeYearsAfterTGE", threeYearsAfterTGE, time.Date(2026, time.October, 30, 0, 0, 0, 0, time.UTC)},
+		{"fourYearsAfterTGE", fourYearsAfterTGE, time.Date(2027, time.October, 30, 0, 0, 0, 0, time.UTC)},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			require.Equal(t, tc.want, tc.got)
+		})
+	}
+}

internal/total_supply_test.go

@@ -17,9 +17,9 @@ func TestTotalSupply(t *testing.T) {
 		{TGE, initialTotalSupplyInUtia},
 		{oneDayAfterTGE, 1000219178082191},
 		{oneYearAfterTGE, 1079999999999715},
-		{twoYearsAfterTGE, 1151791486153206},
-		{threeYearsAfterTGE, 1180338837179088},
-		{fourYearsAfterTGE, 1205929556381924},
+		{twoYearsAfterTGE, 1151643489533809},
+		{threeYearsAfterTGE, 1180266844240616},
+		{fourYearsAfterTGE, 1205860930757792},
 	}
 	for _, tc := range testCases {
 		got := TotalSupply(tc.time)